Seismic Risk Analysis and Design of Nuclear Power Plants

核电站地震风险分析与设计

• 批准号: RGPIN-2018-04031
• 负责人: Xie, WeiChau
• 金额: $ 2.26万
• 依托单位: University of Waterloo
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=669058
• 关键词: Seismic; Risk; Analysis; Design; Nuclear

Earthquakes are among the most destructive natural disasters. In response to the occurrence of several destructive earthquakes in recent decades, the nuclear industry is taking a critical look at the existing methods of assessing seismic risk of nuclear power plants (NPPs). A number of deficiencies have been recognized in the existing methods of seismic risk analysis. ******In an NPP, there are a large number of safety-related structures, systems, and components (SSCs). The most effective approach to ensure safe shutdown and to prevent accidents during an earthquake is to ensure adequate safety margins for these SSCs through seismic design and seismic risk assessment. The long-term objective of my research program is to establish a systematic framework for probabilistic seismic risk analysis and design of NPPs. Through continued collaboration with nuclear industrial partners, the proposed research will satisfactorily address two important issues that have challenged earthquake engineering and the nuclear industry for decades: (1) Generating drift-free, consistent, and perfectly spectra-compatible tri-directional time histories; (2) A direct method for generating Floor Response Spectra (FRS) with flexible foundation and considering soil-structure interaction (SSI).******Time history analysis has been widely used in practice, for example, in nonlinear dynamic analysis and analysis of multi-supported systems. Using eigenfunction expansions and the method of influence matrix, the proposed research will develop an efficient and easy to use algorithm to generate drift-free, consistent, and perfectly spectra-compatible tri-directional ground motion time histories. The algorithms and software developed are of great practical importance in earthquake engineering.******Accurate determination of FRS, used as a seismic input to SSCs, is one of the most critical tasks in seismic analysis. Overly conservative FRS increase the cost, while non-conservative FRS compromise safety. A direct spectra-to-spectra method for generating FRS that is accurate and efficient has recently been developed by my research group. It is suitable for generating FRS for fixed-base structural models and has been successfully applied in a commercial project by Candu Energy Inc. In the proposed research, the direct method will be extended to account for flexible foundation and SSI. The effect of the uncertainty of soil properties on SSI analysis will be accurately addressed and a complete probabilistic method will be developed to model the uncertainty. This research will provide advanced methodologies and modern tools to assess seismic margin and risk of existing SSCs in refurbished NPPs and to design new SSCs in new NPPs to ensure seismic safety.******Close collaborations with the industry will enable HQP to gain both theoretical knowledge and practical experience and make them well qualified for advanced work placements.

地震是最具破坏性的自然灾害之一。为了回应近几十年来发生几次破坏性地震的发生，核工业正在批判地研究评估核电厂（NPP）地震风险的现有方法。 现有的地震风险分析方法已经确认了许多缺陷。 ******在NPP中，有大量与安全相关的结构，系统和组件（SSC）。确保安全关闭并预防地震期间发生事故的最有效方法是通过地震设计和地震风险评估确保这些SSC的足够安全边际。我的研究计划的长期目标是为NPP的概率地震风险分析和设计建立系统的框架。通过与核工业合作伙伴的持续合作，拟议的研究将令人满意地解决两个重要的问题，这些问题挑战了地震工程和核工业数十年来：（1）产生无漂移，一致且完美的频谱兼容的三个方向历史； （2）一种具有柔性基础并考虑土壤结构相互作用（SSI）的直接方法，用于生成地板响应光谱（FRS）。******时间历史分析已在实践中广泛使用，例如，在非线性动态分析和多支撑系统的非线性动态分析和分析中。使用本本特征扩展和影响矩阵的方法，拟议的研究将开发出一种有效且易于使用的算法，以生成无漂移，一致且完美的光谱兼容的三个方向地面运动时间历史。在地震工程中，开发的算法和软件非常重要。******准确地确定FRS（用作SSC的地震输入）是地震分析中最关键的任务之一。过于保守的FRS增加了成本，而非保守的FRS损害了安全性。我的研究小组最近开发了一种用于生成准确有效的FRS的直接光谱对光谱方法。它适用于为固定碱结构模型生成FRS，并已由Candu Energy Inc.成功地应用于拟议的研究中，将扩展该直接方法以说明灵活的基础和SSI。土壤特性对SSI分析的不确定性的影响将准确解决，并将开发出一种完整的概率方法来对不确定性进行建模。这项研究将提供先进的方法和现代工具，以评估翻新的NPP中现有SSC的地震余量和风险，并在新的NPPS中设计新的SSC，以确保地震安全。******与该行业的紧密合作将使HQP能够获得理论知识和实践经验，并使其获得很好的资格获得高级工作安置。